commit d932c7c7fc2c9417524c7ca08f34ee3b18cde41b (tree)
parent b515e40435efda7cfddb8d68b1c4318c0b947bad
Author: Motiejus Jakštys <desired.mta@gmail.com>
Date: Fri, 22 May 2020 10:19:17 +0300
add gpkg samples
Diffstat:
10 files changed, 196 insertions(+), 23 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -18,6 +18,10 @@ __pycache__
*.blg
*.bcf
*.run.xml
+*.gpkg-wal
+*.gpkg-shm
env/
*.pyc
+version.tex
+db/
diff --git a/II/Referatas/Makefile b/II/Referatas/Makefile
@@ -1,2 +1,30 @@
-mj-referatas.pdf: $(shell git ls-files .)
- latexmk -g -pdf mj-referatas.tex
+SHELL = /bin/bash
+
+GEN = zeimena.pdf st-simplify-100.pdf st-simplify-150.pdf st-simplify-300.pdf st-simplify-500.pdf
+
+mj-referatas.pdf: mj-referatas.tex version.tex bib.bib zeimena-pretty.pdf $(GEN)
+ latexmk -g -pdf $<
+
+zeimena.pdf: zeimena.gpkg
+ ./layer2img.py --infile=$< --size=74x52 --outfile $@
+
+st-simplify-%.pdf: db/.faux_st-simplify-%
+ ./layer2img.py --table=douglas_$* --size=74x52 --outfile $@
+
+db/.faux_st-simplify-%: db/.faux_ready st-simplify.sql
+ . ./managedb ; \
+ psql --echo-all -v ON_ERROR_STOP=1 -v tolerance=$* -f st-simplify.sql
+ touch $@
+
+db/.faux_ready: zeimena.gpkg managedb
+ -./managedb stop; rm -fr db
+ ./managedb init
+ ogr2ogr -f PostgreSQL "PG:host=127.0.0.1 user=osm dbname=osm" zeimena.gpkg
+ touch $@
+
+GIT_DIR = $(shell git rev-parse --show-toplevel)/.git
+
+version.tex: $(shell git ls-files .) $(GIT_DIR)
+ date "+%F %T %Z" | awk '{print "\\gdef\\GeneratedAt{"$$0"}%"}' > $@
+ [ -n "$$(git status --porcelain)" ] && suffix="-dirty"; \
+ git describe --tags | awk '{print "\\gdef\\VCDescribe{"$$0"'$$suffix'}%"}' >> $@
diff --git a/II/Referatas/bib.bib b/II/Referatas/bib.bib
@@ -52,7 +52,7 @@
publisher={University of Toronto Press}
}
-// algorithms for generalization, not reaching satisfactory results
+% Algorithms for generalization, not reaching satisfactory results
@inproceedings{monmonier1986toward,
title={Toward a practicable model of cartographic generalisation.},
author={Monmonier, Mark},
@@ -113,7 +113,7 @@
year={2012}
}
-// LIKELY UNNEEDED
+% LIKELY UNNEEDED
@book{buttenfield1991map,
title={Map Generalization: Making rules for knowledge representation},
author={Buttenfield, Barbara Pfeil and McMaster, Robert Brainerd},
diff --git a/II/Referatas/layer2img.py b/II/Referatas/layer2img.py
@@ -3,12 +3,15 @@
import argparse
import geopandas
+import psycopg2
import matplotlib.pyplot as plt
-INCH = 25.4 # mm
+INCH = 25.4 # mm
+
def plt_size(string):
if not string:
+ # using default matplotlib dimensions
return None
try:
w, h = string.split("x")
@@ -16,25 +19,36 @@ def plt_size(string):
except Exception as e:
raise argparse.ArgumentTypeError from e
+
def parse_args():
- parser = argparse.ArgumentParser(description='Convert layer to an image')
- parser.add_argument('infile', type=str)
- parser.add_argument('layer', type=str)
- parser.add_argument('-o', '--output', metavar='<file>', type=str)
- parser.add_argument('--size', type=plt_size, help='Figure size in mm (WWxHH)')
+ parser = argparse.ArgumentParser(
+ description='Convert geopackage to an image')
+ group = parser.add_mutually_exclusive_group(required=True)
+ group.add_argument('--infile', type=str)
+ group.add_argument('--table', type=str)
+ parser.add_argument('-o', '--outfile', metavar='<file>', type=str)
+ parser.add_argument(
+ '--size', type=plt_size, help='Figure size in mm (WWxHH)')
return parser.parse_args()
+
def main():
args = parse_args()
- f = geopandas.read_file(args.infile)
+ if args.table:
+ conn = psycopg2.connect("host=127.0.0.1 dbname=osm user=osm")
+ sql = "SELECT geom FROM %s" % args.table
+ f = geopandas.read_postgis(sql, con=conn, geom_col='geom')
+ else:
+ f = geopandas.read_file(args.infile)
f.plot(figsize=args.size)
plt.axis('off')
plt.margins(0, 0)
plt.tight_layout(0)
- if args.output:
- plt.savefig(args.output, bbox_inches=0, dpi=300)
+ if args.outfile:
+ plt.savefig(args.outfile, bbox_inches=0, dpi=300)
else:
plt.show()
+
if __name__ == '__main__':
main()
diff --git a/II/Referatas/managedb b/II/Referatas/managedb
@@ -0,0 +1,46 @@
+#!/bin/bash
+
+main() {
+ PATH=$PATH:/usr/lib/postgresql/12/bin
+ case ${1:-} in
+ init)
+ mkdir -p db && initdb db
+ mkdir -p db/wal
+ sed -i "s/.*unix_socket_dir.*/unix_socket_directories = '.\/wal'/" \
+ db/postgresql.conf
+ pg_ctl -D db -l db/logfile start
+
+ export PGHOST=127.0.0.1
+ psql postgres -c 'CREATE ROLE osm WITH SUPERUSER LOGIN'
+ psql postgres -c 'CREATE DATABASE osm'
+ psql osm osm -c 'CREATE EXTENSION postgis'
+ ;;
+ start)
+ pg_ctl -D db -l db/logfile start
+ ;;
+ stop)
+ pg_ctl -D db -l db/logfile stop
+ ;;
+ *)
+ >&2 echo "Unknown command: '$*'"
+ exit 1
+ ;;
+ esac
+}
+
+if [[ "${BASH_SOURCE[0]}" != "${0}" ]]; then
+ if [[ $# != 0 ]]; then
+ >&2 echo "Sourcing does not accept arguments: $*"
+ else
+ export PGHOST=127.0.0.1
+ export PGUSER=osm
+ export PGDATABASE=osm
+ >&2 echo "OK: exported PGUSER, PGHOST and PGDATABASE"
+ fi
+else
+ set -euo pipefail
+ export PGHOST=
+ export PGUSER=
+ export PGDATABASE=
+ main "$@"
+fi
diff --git a/II/Referatas/mj-referatas.tex b/II/Referatas/mj-referatas.tex
@@ -14,6 +14,7 @@
\usepackage{varwidth}
\usepackage{tikz}
\usetikzlibrary{er,positioning}
+\input{version}
\title{
Cartografic Generalization of Lines \\
@@ -21,15 +22,40 @@
}
\iffalse
+small scale: 1:XXXXXX
+large scale: 1:XXX
+
+take douglas-pecker and check for different scales.
+
a4: 210x297mm
a6: 105x148xmm
a7: 74x105mm
a8: 52x74mm
+
+connect rivers first to a single polylines:
+- some algs can preserve connectivity, some not.
+
+ideal hypothesis: mueller algorithm + topology may fully realize cartographic generalization tasks.
+
+what scales and what distances?
+
+https://postgis.net/docs/ST_SimplifyVW.html
+https://postgis.net/docs/ST_Simplify.html
+https://postgis.net/docs/ST_SimplifyPreserveTopology.html
+
+how is tolerance bound to scale?
+- just use same parameter.
+
+
\fi
\author{Motiejus Jakštys}
-\date{\today}
+\date{
+ \vspace{10mm}
+ Version: \VCDescribe \\ \vspace{4mm}
+ Generated At: \GeneratedAt
+}
\begin{document}
\maketitle
@@ -73,7 +99,7 @@ of straight and curved river shape, and author's familiarity with the location.
\begin{figure}
\centering
- \includegraphics[width=148mm]{zeimena}
+ \includegraphics[width=148mm]{zeimena-pretty}
\caption{Žeimena near Jaunadaris}
\label{fig:zeimena}
\end{figure}
@@ -81,19 +107,60 @@ of straight and curved river shape, and author's familiarity with the location.
\section{Mathematical and geometrical algorithms}
To understand why geometrical algorithms are not entirely suitable for
-downscaling, let's pick some visual examples.
-
-\subsection{Douglas \& Peucker}
+downscaling, let's pick some visual examples. Start with
+\cite{douglas1973algorithms}, one of the most well-known line simplification
+algorithms, which is often used for generalization. Žeimena example is
+generalized with different tolerances in figure~\ref{fig:douglas-peucker} on
+page~\pageref{fig:douglas-peucker}.
-\cite{douglas1973algorithms} is one of the most well-known line simplification
-algorithms, which is often used for generalization. It will simplify the line shape.
+As one can observe in figure~\ref{fig:douglas-100}, the Douglas \& Peucker with
+100m tolerance preserves most of the shape, and 500m
+(figure~\ref{fig:douglas-500}) becomes a straight line.
-Trying the same dataset with different tolerances for Douglas \& Peucker.
+\begin{figure}
+ \centering
+ \begin{subfigure}[b]{0.18\textwidth}
+ \includegraphics[width=\textwidth]{zeimena}
+ \caption{original}
+ \label{fig:zeimena-original}
+ \end{subfigure}
+ ~
+ \begin{subfigure}[b]{0.18\textwidth}
+ \includegraphics[width=\textwidth]{st-simplify-100}
+ \caption{100m}
+ \label{fig:douglas-100}
+ \end{subfigure}
+ ~
+ \begin{subfigure}[b]{0.18\textwidth}
+ \includegraphics[width=\textwidth]{st-simplify-150}
+ \caption{150m}
+ \label{fig:douglas-150}
+ \end{subfigure}
+ ~
+ \begin{subfigure}[b]{0.18\textwidth}
+ \includegraphics[width=\textwidth]{st-simplify-300}
+ \caption{300m}
+ \label{fig:douglas-300}
+ \end{subfigure}
+ ~
+ \begin{subfigure}[b]{0.18\textwidth}
+ \includegraphics[width=\textwidth]{st-simplify-500}
+ \caption{500m}
+ \label{fig:douglas-500}
+ \end{subfigure}
+ \caption{Douglas \& Peucker line simplifications with different tolerances}
+ \label{fig:douglas-peucker}
+\end{figure}
\section{Algorithms based on cartographical knowledge}
-\cite{jiang2003line}, \cite{dyken2009simultaneous},
-\cite{mustafa2006dynamic}, \cite{nollenburg2008morphing}
+For further investigation:
+\begin{itemize}
+ \item \cite{jiang2003line}
+ \item \cite{dyken2009simultaneous}
+ \item \cite{mustafa2006dynamic}
+ \item \cite{nollenburg2008morphing}
+\end{itemize}
\section{My Idea}
\label{sec:my_idea}
diff --git a/II/Referatas/st-simplify.sql b/II/Referatas/st-simplify.sql
@@ -0,0 +1,14 @@
+DROP TABLE IF EXISTS douglas_:tolerance;
+
+CREATE TABLE douglas_:tolerance (
+ fid serial NOT NULL,
+ geom geometry(MULTILINESTRING, 3346)
+);
+
+INSERT INTO douglas_:tolerance (geom) (
+ SELECT
+ ST_Simplify (ST_LineMerge (ST_Union (geom)),
+ :tolerance) AS geoms
+ FROM
+ zeimena);
+
diff --git a/II/Referatas/zeimena-pretty.pdf b/II/Referatas/zeimena-pretty.pdf
Binary files differ.
diff --git a/II/Referatas/zeimena.gpkg b/II/Referatas/zeimena.gpkg
Binary files differ.
diff --git a/II/Referatas/zeimena.pdf b/II/Referatas/zeimena.pdf
Binary files differ.
